Automatic automatic manipulator of the above-described type, such as multiaxial industrial robots, hereinafter called robots for short, are regularly used in the food industry and the pharmaceutical industry, as in many other branches of industry as well. It shall be ensured because of the strict hygienic regulations applicable that the robots used do not become a source of contamination of their working environment. Such contamination is caused, on the one hand, by lubricant or abraded particles, which are released from the interior the robot and enter the environment. On the other hand, the robot is always contaminated in the working areas from the outside, for example, by food residues and/or moisture, which may lead to contamination of and/or damage to the robot.
To avoid the above-mentioned problem, it was proposed in EP 0 937 551 A1 that the frame and the carousel of a multiaxial industrial robot be surrounded with a covering made of a material that is insensitive to the external effects and is easy to clean, such as stainless steel or the like. The fact that the covering provided additionally represents an extra design effort (in terms of the material), which is associated with correspondingly increased manufacturing costs, shall be considered to be particularly disadvantageous in such a solution. In addition, additional parts of the robot, such as the rocker, the robot arm or the robot hand, continue to be unprotected, and they represent a potential risk for contamination.
WO 96/08347 shows a robot arm arrangement that is surrounded with washable housing parts having a smooth surface for cleaning purposes. The above-described drawbacks occur in this case as well.
Furthermore, it was proposed in EP 0 988 939 A1 that exposed surfaces of an industrial robot be coated with a layer consisting of a synthetic resin or the like, which has antimicrobial components. The additional step of coating the robot represents a disadvantageous extra cost for preparing the coating in this case as well. Furthermore, the protective action of such a coating may decline over time and after repeated cleaning operations, e.g., with high-pressure cleaning devices. Moreover, a local damage to the protective coating is possible.